Motor disconnect sizing questions

[magic_smoke]

Hi,

First off, thank you very much for the opportunity to join the forum. I realize the are some very talented people in these forums.

I recently purchased a new compressor and I am trying I to size a disconnect for the motor

Motor specs:

Baldor
5hp
Single phase
240v
23 amps (nameplate)

From table 430 in NEC the flc for a 5hp single phase motor is 28 amps. Taking 115% of the flc produces 32 amps. I am curious because there are a lot of disconnects are rated at 30 amps and 5hp @ 240v. How is this?

Also it appears that most of the disconnects are sized for #8-10 awg. I ran #6 awg for the feeder circuit (magnetic starter/overload protection is wired with #8 awg. I am having a hard time finding a disconnect that will work for this application. The disconnect needs to accommodate #6 and #8awg. Do you guys have any recommendations?

 

[infinity]

What about 430.110(A)Ex?

 

[jumper]

Cheap 60A non-fused disconnects are pretty common.

http://www.lowes.com/Electrical/Loa...TopFlexible_Area-_-180108_20_Safety_Switches#!

 

[Jraef]

Hi,

.... I am curious because there are a lot of disconnects are rated at 30 amps and 5hp @ 240v. How is this?

I think you are looking at the 240V 3phase rating of a 30A FDS. The 2 pole 240V single phase HP rating on every one I look at is 3HP. You need a 60A switch, which will then allow for the appropriate wire size.

 

[magic_smoke]

Thanks for the link and the info. I am not sure why was not able to find those cheaper 60 amp disconnects (all the ones I saw were $500+). I really appreciate it. I think I am going to my local Lowe's tonight to pick one up.